There is evidence that it is better to continue chemotherapy than stop it in metastatic breast cancer. A systematic review identified four randomised trials comparing more with fewer cycles of the same chemotherapy in women with advanced breast cancer. Meta-analysis of these four trials including 766 women showed a modest, survival advantage for women randomized to more cycles of chemotherapy (median survival 23% longer with more cycles, p = 0.01). Quality of life was also better with more cycles of chemotherapy than fewer in the one trial that measured it. The combined evidence from these trials supports a policy of continuing chemotherapy in the absence of disease progression or significant side effects. Much of this work was done in the 1990′s and the issue in our time is more how to sequence chemotherapy than how long to continue it; hence, the question ahs not been addressed experimentally in recent years. However, it is generally accepted that chemotherapy should be continued past remission or stablilization. At the same time, in this case, after 30 cycles of continued chemotherapy farther chemotherapy is not medically necessary until the existence of metastatic disease is proven. At some point contnued therapy turns into maintenance therapy, which is a different concept and needs to be proven for breast cancer (In some older trials, before a wider emergence of the concept of maintenance, what nwo would be called continued or extended chemotehrapy was called maintenance). There is some evidence that Doxil can be benefical as maintenance. There is an ongoing trial: Maintenance Chemotherapy in Metastatic Breast Cancer ,NCT00289263. This is a randomized, prospective and multicenter phase III study. Two-hundred-sixty-two (262) patients on each arm will be recruited in the study.
Martin R Stockler et al, Therapy for Advanced Breast Cancer – How Long Should it Continue?
Journal Breast Cancer Research and Treatment Volume 81, Supplement 1 / March, 2003
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